1. Field of the Invention
The present invention relates to a terminal device to which a storage device is mounted, and a storage device fastening mechanism for fastening the storage device. Particularly, it relates to a terminal device, which generates vibration during operation, such as a POS (Point-Of-Sales) terminal device. The vibration accompanies the opening/shutting operation of a drawer.
Most of recent terminal devices such as a computer or others necessarily have, as a storage device, a magnetic storage device (file disk) such as a hard disk drive (HDD) or a floppy disk drive (FDD). To mount such a storage device to the terminal device, various mechanisms have been adopted.
2. Description of the Related Art
The file disk reads information recorded on a magnetic disk and records information thereon, while rotating the magnetic disk by a motor, using a magnetic head attached to an arm which is driven to rotate about a pivot.
If vibration or shock is externally applied to the terminal device mounting such a storage device thereon during the reading or recording of information, the magnetic head may deviate from the proper position to cause the incorrect reading/recording of information or touch a surface of the magnetic disk, on which information is recorded, to damage the information.
A POS terminal device will be described below as an example of a terminal device which frequently generates vibration. The POS terminal device has a drawer for holding cash therein to transfer the same between customers and the operator. The drawer is normally closed, but temporarily made to open for the purpose of cash delivery/acceptance when one sale has been over, and then is shut again by the operator.
Due to this opening/shutting operation of the drawer, a relatively large vibration occurs in the POS terminal device. Particularly, when the drawer is open, the vibration is considerable because a spring force is used for this purpose. On the other hand, to record a history of sales carried out in the POS terminal device, a disk file device is provided in the POS device. Since the disk file device is often accommodated in a controller section provided on the drawer, the read error on the disk or the like may frequently occur due to shock caused by the opening/shutting of the drawer.
Such a problem is not limited to the POS terminal device but is common to generally used personal computers or others if they are located in the vicinity of a vibration source or in an environment wherein a relatively intense vibration is liable to be transmitted to the computer body. Under the circumstances, the disk device in the personal computer may be broken as in the POS terminal device.
To prevent the vibration from being transmitted to the storage device, various proposals have been made in the prior art.
In FIGS. 22A and 22B, a conventional structure for securing a magnetic disk device to a terminal device is illustrated. In the structure shown in FIGS. 22A and 22B, the magnetic disk device is not directly attached to a base plate of a terminal device, but is once attached to a frame which in turn is fastened to the base plate.
The frame consists of a frame B for mounting the magnetic disk device and a frame A attached to the frame B as a cover.
On the bottom surfaces of HDDs, and FDDS, screw holes are provided for screw-fastening these magnetic disk devices. These magnetic disk devices are fastened to the frame B via the screw holes. If the magnetic disk device is directly mounted to the frame B, external vibration may be transmitted to the magnetic disk device. Therefore, a countermeasure thereto is necessary.
According to the structure shown in FIGS. 22A and 22B, a steel collar spacer is inserted into a central hole of a grommet made of an elastic material such as rubber, which in turn is fitted into a screw hole of the frame B. The magnet disk device is placed on the grommet and screw-fastened. Since the grommet is capable of absorbing shock by its elasticity, it is possible to mitigate shock caused by the opening/shutting of drawer and reduce the magnitude of shock transmitted to the magnetic disk device.
FIGS. 23A and 23B illustrate another conventional structure for fastening a magnetic disk device. In this structure, the magnetic disk device is attached to a frame corresponding to the frame A shown in FIGS. 22A and 22B.
The frame has screw holes for fastening the magnetic disk device on the opposite side surfaces thereof. Also, in the structure shown in FIGS. 23A and 23B, since the magnetic disk device is attached via the grommets and the collar spacers, it is possible to minimize vibration directly transmitted to the magnetic disk device.
In the conventional structures shown in FIGS. 22A, 22B, 23A, and 23B, however, fastening of the magnetic disk device to the frame or fastening of the frame to the base plate is carried out using screws, which results in the increase in the number of parts necessary for fastening the magnetic disk device, causing problems in that the man-hours necessary for the assembly, or the dismounting for the purpose of maintenance, increase. Also, manufacturing cost rises as the number of parts increases.
The above method for mounting the magnet disk device to the frame requires the use of a metallic plate, which results in an increase in the frame cost.
Accordingly, an object of the present invention is to provide a terminal device and a storage device fastening mechanism, capable of avoiding the adverse effect of external shock on the storage device.
Another object of the present invention is to realize a storage device fastening mechanism easily attachable/detachable to a terminal device, having a smaller number of parts, and the terminal device incorporating such a mechanism therein.
Also, a further object of the present invention is to realize a fastening mechanism for a storage device which is easily manufactured at a low cost.